3x(2x+5)+(6x-1)(2-x)+2
=>6x2+15x-6x2+x+12x-2+2
=>27x
\(3x\cdot\left(2x+5\right)+\left(6x-1\right)\cdot\left(2-x\right)+2\\ \Leftrightarrow6x^2+15x+12x-6x^2-2+x+2\\ \Leftrightarrow28x\)
Violympic toán 8
Các câu hỏi tương tự
d) (5x+3) ( 4x-1) +(10x-7) (-2x+3) =27
e)(8x-5) (3x+2) -(12x+7) (2x-1)=17
f) (5x+9) (6x-1) -(2x-3)( 15z+1) = -190
g) 6x(5x+3) + 3x(1-10x) =7
h) (3x-3) (5 -21x) +(7x+4)(9x-5) =44\
i) (x+1)(x+2)(x-5)-x2 (x+8)=27
1) x ² + 2x -4 = -12 + 3x + x ²
2) x( 2x - 3 ) - x ² + 2 = x(x - 5) - 1
3) (x-1)(x+3) = x² -4
4) (6x + 2)(x-2) = 2x(3x-5)
5) (x-2) ² = (x-3)(x+2)
Bài 1: giải các phương trình sau
a,(3x-1)(x+3)=(2-x)(5-3x) d,(3x+5)(2x+1)=(6x-2)(x-3)
b,(x+5)(2x-1)=(2x-3)(x+1) e,(x+2)2+2(x-4)=(x-4)(x-2)
c,(x+1)(x+9)=(x+3)(x+5) f,(x+1)(2x-3)-3(x-2)=2(x-1)2
Tìm
Min A= 3x^2+2x+7/x^2+2x+3
Max B= 2x^2-16x+29/x^2-6x+10
Min C = 6x^2-14x+29/x^2-2x+5
Max D = 5x^2+2x+2/x^2+x+1
bài 2: làm tính chia
a. (x^3-3x^2+x_3):(x-3)
b. (x^2+2x+x^2-4):(x+2)
c.(2x^3-5x^2+6x-15):(2x-5)
d. (x^3+2x^2-2x-1):(x^2+3x+1)
Giải các phương trình :
a) (2x + 5)2 = (x + 2)2
b) 2x3 + 6x2 = x2 + 3
c) 1 + 1/x +2 = 12/ 8 - x3
d) 2(1-2x)/4 - 2 + 3x/6 = 2 - 2(3x -1)/ 2
e) (x - 2)(2x - 3) = (4 - 2x)(x - 2)
f) 2x( x - 3) + 5(x - 3) = 0
g) 4x2 - 1 = (2x + 1)(3x - 5)
Câu 1:
a) (x+2) (x+3) -(x-2) (x+5)=0
b) (2x +3) (x-4) + (x-5) (x-2) = (3x-5) (x-4)
c) (3x +2) (2x+9) - ( x+2) (6x+1) = x+1 - (x-6)
d) 3( 2x-1) (3x-1) - (2x-3) (9x-1)= 0
Các bạn cố gắng giúp mik nha!
Thank you very much!
Bài 1 : tìm x biết
A. 3x2.(2x3-x+5)
B. (4xy+3y-5x).x2+7
C. (3x-2)(4x+5)-6x(2x-1)
D. (3x-5)(x2-5x+7)
1. Làm tính nhân, chia:
a. (x5 + 4x3 - 6x2) : 4x2
b. (x3 - 8) : (x2 + 2x + 4)
c. (3x2 - 6x) : (2 - x)
d. (x3 + 2x2 - 2x - 1): (x2 + 3x + 1)
2. Tìm x, biết:
a. (x - 4)2 - (x - 2)(x + 2) = 6
b. 9 (x + 1)2 - (3x - 2)(3x + 2) = 10